Labor-intensive industries, such as mining, manufacturing, landscaping, and the like, often transport personnel, equipment, and materials between locations at work facilities. Manufacturing and warehouse facilities, as well as other businesses, use forklift trucks for lifting and moving pallets of products and materials, often to and from loading docks, storage racks, and point-of-use of the products and materials. Mining, in particular, faces transport problems that involve not only movement of personnel but movement of tools and equipment, and excavated waste materials and ore. Mines often have long corridors or passageways leading from mine entrances to the mining face for ore extraction. Other passageways link the various mining chambers. The passageways are opened by drilling and excavation. The surface of the passageway on which persons walk or are transported typically are rough, similar to an above-ground gravel road scraped in the surface of the ground. The passageways are not paved for smooth movement of persons and transport vehicles.
Movement of transit vehicles along the passageways is slow. Many mines have speed limits for safety purposes as the vehicles travel through the dimly-lit passageways. In addition, the rough surface of the passageway limits transport speeds. However, transport vehicles for use in mines are constructed for functional purposes and not the comfort of the operator and personnel traveling on the vehicles. The vehicles typically have a chassis formed of box beams. Axles attach rigidly to the chassis. As a consequence, jolts and bumps experienced by the vehicle moving on the rough and uneven floor surface of the passageway communicate directly through the chassis to the occupants operating the vehicle or being transported by the vehicle. While reduced speed lessens the jostling and pounding experienced by the vehicle occupants, reduced speed is not entirely satisfactory. For single-occupant vehicles, such as a load hauler or equipment carrier, air-dampened suspension seats are typically installed in the vehicle. The suspension seats dampen and cushion the rough ride. Nevertheless, the vehicle operator still experiences significant jostling and bumping as the vehicle moves through the passageways.
Accordingly, there is a need in the art for an improved suspension system for low occupancy, low speed vehicles. It is to such that the present invention is directed.